Firearms frequently include a sight designed to assist the user in the accurate aiming of the firearm. One type of sight is a so called “iron sight” which may be provided on the top of the firearm and may include a pair of vertically extending guides or pillars. A user would utilize the sight by aligning the sightline of a downfield target between the vertically extending guides. A properly calibrated, or zeroed, sight would allow the user to accurately hit a down field target when aligned within the sight. Zeroing, or adjusting, the sight allows the user to change the orientation of the sight to ensure accurate aiming of the firearm.
FIG. 13 illustrates a common sight adjustment mechanism included in some firearms, such as an AR-15 rifle. The sight adjustment mechanism 10 may include a detent or pin 20 and a rotating wheel 30 having a plurality of circumferential grooves 32 as well as a vertical protrusion 34. Rotation of wheel 30 results in adjustment of the sight. Pin 20 may be compressible between a deployed position and a compressed position, with the deployed position serving as the default or at rest position of pin 20. Grooves 32 may have a corresponding dimension with pin 20 such that pin 20 in the deployed position fits within one of the grooves 32 thereby preventing the rotation of wheel 30. In order to adjust the sight, pin 20 would need to be compressed so as to permit free rotation of wheel 30. Without an adjustment tool, the combination of compressing pin 20 and rotating wheel 30 can be difficult. Moreover, while grooves 32 may be evenly disbursed along the circumferential edge of wheel 30, for instance at 90 degree intervals, the user may easily and unintentionally over rotate wheel 30 while pin 20 is compressed. In some instances, sight adjustment mechanism 10 may sit within a channel 40 defined by channel edges 42 on either side of sight adjustment mechanism 10.